What is "ha'Keriyos"?
Rashi: It is the name of the city. Radak - we find "v'Al Keriyos v'Al Batzrah" (verse 24). Even though names do not normally have Yedi'ah (the prefix Hei 1 to identify), we find like this - "ba'Karkar" (Shoftim 8:10), "ba'Sukos 2 ".
Radak: They are the cities in the plain. The Metzudos are on high places.
Malbim: They are very fortified cities.
A Patach under the prefix Beis, Kaf or Lamed is in place of the prefix Hei. (PF)
Refer to Shmuel I, 15:4:2:2*.
Why does it say "Nilchedah" (singular)? Ha'Keriyos is plural!
Radak: All the cities will be conquered quickly, like one, and all the fortresses at once (therefore also Nispasah is singular).
What is "Ishah Metzerah"?
Radak, Targum Yonasan: A woman in birth-pangs 1 , when she bends to give birth. Radak - Metzerah is like "uch'Hetzar Lo" (Divrei ha'Yamim II, 33:12). She is in pain, and stands in affliction.
Malbim: Women are generally weak, and especially when she is afflicted in pain.
